Variable exhaust fok steam-engines



HURLBERT, OF NORTHFIELD, VERMONT.

VARIABLE EXHAUST FOR STEAM-ENGINES.

Specification of Letters Patent No. 25,509, dated September 20, 1859.

T o all whom it may concern:

Be it known that I, XVILLIAM M. HURL.- BERT, of Northfield, in the county of Vashington and State of Vermont, have invented a new and Improved Arrangement of Slides for Varying the Area of Opening of the ExliaustNozzles of Locomotives; andI do hereby1 declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure 1, exhibits a transverse vertical section of the smoke box of a locomotive with an outside View of the blast pipes. Fig. 9., is a section of the exhaust pipes and regulating slides in a plane parallel with Fig. l. Fig. 3, is a horizontal section of the smoke-box, nozzles and regulating` slides.

Similar letters of reference indicate corresponding parts in the several figures.

My invention consists in making the upper ends or nozzles of the blast pipes each in the form of an elbow or the inverted letter l., and fitting the regulating slides to the horizontal portions of the elbows substantially as herein described.

To enable others skilled in the art to make and use my invention I will proceed to` describe its construction and operation.

A is the smoke box and B, B are the tubes of the boiler.

C, O, are the blast pipes arranged vertically side by side under the chimney H.

D, D, are the elbow shaped nozzles fitted and secured to the mouth of the pipes and having openings a, o, in the top above the blast pipes. The horizontal portions of the elbows turn outward and are open, and have the slides E, E, inserted at their outer These slides lit the horizontal poren ds.

tions of the elbows, and may be of cylindrical, square or other form in their trans verse section, but are represented cylindrical, and made hollow for the sake of lightness. Their inner ends are closed and beveled on their under sides.

F, is a shaft fitted to rotate in bearings (Z, d, provided on the elbows D, D, but con ned longitudinally and having upon it two screw threads b, one right and the other left handed, said threads being fitted to corresponding female screws provided in lugs c, c, on the slides. The said shaft protrudes through the outside of the smoke box where it is geared by a pair of bevel gears I, J, with a shaft G, which extends to the engineers platform where it is furnished with a hand crank to turn it in either direction for the purpose of turning the screw shaft F, and so adjusting the slides to cover or uncover' a greater or less portion ofthe openings, a, a, and so regulate the exhaust, both sides being operated in a corresponding manner by the screwthreads on the shaft F. This mode of applying the slides makes a very simple and effective arrangement for varying the area of the openings of the nozzles.-

I do not confine myself to the means herein described of operating the slides. But

That I claim as my invention and desire to secure by Letters Patent is- Applying the slides to operate in elbows or inverted L-shaped nozzles arranged substantially as herein described.

lV. M. HURLBERT.

itnesses E. F. PERKINS, T. A. MILES. 

